The invention relates, for example, to rotary duplicator machines provided with a rotating printing drum on which is mounted a printing form bearing a transferrable image in the form of a multi-line text. A counterpressure roller can be swung towards and away from the printing drum, to effect transfer of the whole text on the printing form to sheets transported between the drum and counterpressure roller, and to effect transfer of individual lines and/or combinations of lines from the text to smaller-format cards being transported between the drum and counterpressure roller.
In machines of this type, the whole-page sheets to be printed and the smaller-format cards to be printed are fed to the printing drum by means of separate respective feeders. Typically, the whole-page sheets are fed in one by one from a stack of such sheets. It is known to arrange the card feeder upon the infeed plate of the sheet feeding arrangement. However, with this known approach, when a stack of cards is in place in the card feeder, it is not possible or else extremely awkward to effect feeding of the whole-page sheets. Typically, after some cards have been printed, the stack of cards in the card feeder must be removed in order to set up the feeder for infeed of whole-page sheets.
Attempts have been made to avoid this kind of difficulty by locating the feeder for the smaller-format cards or slips beneath the infeed plate for the whole-page sheets. The feeders for the sheets and cards (or slips) are alternatively and selectably activated, and when activated cause a whole-page sheet or smaller-format card to be fed to the printing location by means of common transport rollers. The difficulty with that approach is that it is not simple to feed in cards of differing types. If cards of different types are to be fed into the printing station in a predetermined sequence, then it is actually necessary to arrange blank cards of the required types, in the required numbers and sequences in a stack, and to insert that stack into the card feeder; only in that sense can such more complicated card variety sequences be printed.